geirm 01/03/16 15:27:04
Modified: docs developer-guide.html
Log:
follows xml
Revision Changes Path
1.31 +46 -17 jakarta-velocity/docs/developer-guide.html
Index: developer-guide.html
===================================================================
RCS file: /home/cvs/jakarta-velocity/docs/developer-guide.html,v
retrieving revision 1.30
retrieving revision 1.31
diff -u -r1.30 -r1.31
--- developer-guide.html 2001/03/15 12:49:44 1.30
+++ developer-guide.html 2001/03/16 23:27:01 1.31
@@ -685,10 +685,19 @@
For advanced users, the VelocityServlet base class allows you to override parts of
the handling of the request processing. The following methods may be overridden.
<ul>
- <li> <code>Context createContext(HttpServletRequest request, HttpServletResponse
response )</code>
+ <li> <code> Properties loadConfiguration(ServletConfig config )</code><br />
+ Allows you to override the normal configuration mechanism and add or alter
the configuation properties. This is
+ useful for overriding or augmenting template and log paths, to set the
absolute path into the webapp root
+ at runtime.
+ </li>
+ <li> <code>Context createContext(HttpServletRequest request, HttpServletResponse
response )</code><br />
Allows you to create the Context object yourself. This allows more advanced
techniques, such as chaining
or pre-loading with tools or data. The default implementation simply returns a
VelocityContext
- object with the request and response objects placed inside.
+ object with the request and response objects placed inside. The request and
response objects are wrapped
+ in simple wrapper classes to avoid introspection problems that may occurr in
some servlet container
+ implementations. You can use the request and repsponse objects normally,
accessing methods of either
+ from the template. Just note that they aren't specifically javax.servlet.XXXX
classes, if that is important
+ to you.
</li>
<li> <code>void setContentType( HttpServletRequest request, HttpServletResponse
response )</code>
Allows you to examine the request and set the content type yourself, depending
on the request or
@@ -703,6 +712,11 @@
Allows you to do any cleanup or resource reclamation at the end of the request
processing. The default
does nothing.
</li>
+ <li> <code>protected void error( HttpServletRequest request, HttpServletResponse
response, Exception cause )</code><br />
+ Error handler that is called an exception occurrs in request processing.
Default implementation will
+ send a simple HTML message with stacktrace and exception information back to
the user. Override for
+ custom client messages and more advanced problem handling.
+ </li>
</ul>
For further information, please see the Javadoc <a href="apidocs/index.html">API
documentation</a>.
@@ -824,21 +838,36 @@
of what they do :
<ul>
-<li> <code> evaluate( Context context, Writer out, String logTag, String instring
)</code><br />
-<code>evaluate( Context context, Writer writer, String logTag, InputStream instream
)</code><br />
-These methods will render the input, in either the form of String or InputStream to
an output Writer, using a Context that you
-provide. This is a very convenienient method to use for token replacement of
strings, or if you keep 'templates' of VTL-containing
-content in a place like a database or other non-file storage, or simply generate
such dynamically.</li>
-<li><code>invokeVelocimacro( String vmName, String namespace, String params[],
Context context, Writer writer )</code><br />
-Allows direct access to Velocimacros. This can also be accomplished via the
<code>evaluate()</code> method above if you wish. Here
-you simply name the vm you wish to be called, create an array of args to the VM, a
Context of data, and Writer for the output.
-Note that the VM args must be the 'keys' of the data objects in the Context, rather
than literal data to be used as the arg. This
-will probably change.</li>
-<li><code>mergeTemplate( String templateName, Context context, Writer writer
)</code><br />
-Convenient access to the normal template handling and rendering services of
Velocity. This method will take care of getting and
-rendering the template. It will take advantage of loading the template according
to the properties setting for the file resource
-loader, and therefore provides the advantage of file and parsed template caching
that Velocity offers. This is the most efficient
-way to access templates, and is recommended unless you have special needs.</li>
+ <li>
+ <code> evaluate( Context context, Writer out, String logTag, String instring
)</code><br />
+ <code>evaluate( Context context, Writer writer, String logTag, InputStream
instream )</code><br />
+ These methods will render the input, in either the form of String or
InputStream to an output Writer,
+ using a Context that you provide. This is a very convenienient method to use
for token replacement of
+ strings, or if you keep 'templates' of VTL-containing content in a place like
a database or other
+ non-file storage, or simply generate such dynamically.
+ </li>
+
+ <li>
+ <code>invokeVelocimacro( String vmName, String namespace, String params[],
Context context, Writer writer )</code><br />
+ Allows direct access to Velocimacros. This can also be accomplished via the
<code>evaluate()</code> method above
+ if you wish. Here you simply name the vm you wish to be called, create an
array of args to the VM,
+ a Context of data, and Writer for the output. Note that the VM args must be
the 'keys' of the data
+ objects in the Context, rather than literal data to be used as the arg. This
will probably change.
+ </li>
+
+ <li>
+ <code>mergeTemplate( String templateName, Context context, Writer writer
)</code><br />
+ Convenient access to the normal template handling and rendering services of
Velocity. This method will take
+ care of getting and rendering the template. It will take advantage of loading
the template according
+ to the properties setting for the file resource loader, and therefore provides
the advantage of file
+ and parsed template caching that Velocity offers. This is the most efficient
way to access templates,
+ and is recommended unless you have special needs.
+ </li>
+
+ <li>
+ <code> boolean templateExists( String name ) </code><br />
+ Determines if a template <code>name</code> is able to be found by the currently
configured resource loaders.
+ </li>
</ul>
</p>
<p>
